{
  "document": {
    "acknowledgments": [
      {
        "summary": "This vulnerability was found by Emre Demirors of Cisco during internal security testing."
      }
    ],
    "category": "csaf_security_advisory",
    "csaf_version": "2.0",
    "notes": [
      {
        "category": "summary",
        "text": "A vulnerability in the firmware of the Cisco UCS C-Series Rack Servers could allow an authenticated, physical attacker to bypass Unified Extensible Firmware Interface (UEFI) Secure Boot validation checks and load a compromised software image on an affected device.\r\n\r\nThe vulnerability is due to improper validation of the server firmware upgrade images. An attacker could exploit this vulnerability by installing a server firmware version that would allow the attacker to disable UEFI Secure Boot. A successful exploit could allow the attacker to bypass the signature validation checks that are done by UEFI Secure Boot technology and load a compromised software image on the affected device. A compromised software image is any software image that has not been digitally signed by Cisco.\r\n\r\n\r\nThere are no workarounds that address this vulnerability. Cisco has released firmware updates that address this vulnerability.\r\n\r\nThis advisory is available at the following link:\r\nhttps://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200219-ucs-boot-bypass [\"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200219-ucs-boot-bypass\"]",
        "title": "Summary"
      },
      {
        "category": "general",
        "text": "This vulnerability affects the following Cisco products if they are running a vulnerable BIOS version and a vulnerable Cisco Integrated Management Controller (IMC) firmware release:\r\n\r\nFirepower Management Center (FMC) 1000\r\nFirepower Management Center (FMC) 2500\r\nFirepower Management Center (FMC) 4500\r\nSecure Network Server 3500 Series Appliances\r\nSecure Network Server 3600 Series Appliances\r\nThreat Grid 5504 Appliance\r\n\r\nUEFI Secure Boot is enabled only in a small subset of Cisco UCS-based appliances. For all the other appliances, the feature is not used, so the vulnerability does not apply.\r\n\r\nFor information about which BIOS versions and firmware releases are vulnerable, see the Fixed Software [\"#fs\"] section of this advisory.",
        "title": "Vulnerable Products"
      },
      {
        "category": "general",
        "text": "Only products listed in the Vulnerable Products [\"#vp\"] section of this advisory are known to be affected by this vulnerability.",
        "title": "Products Confirmed Not Vulnerable"
      },
      {
        "category": "general",
        "text": "UEFI Secure Boot was created to enhance security in the pre-boot environment. The core issue is ensuring that a system boots without introducing compromised code.\r\n\r\nEnsuring that boot code is executed without modification requires the use of a digital signature that is provided by a trusted code creator and embedded in every executable code section. Using public/private key pairs, the code creator \u201csigns\u201d their code with a private key, which can be checked against a public key in a pre-stored signature before it is executed.\r\n\r\nBecause of the UEFI Secure Boot feature, the software images for the affected products are all signed by the Cisco development teams to ensure that they have not been tampered with.\r\n\r\nFor more details on the UEFI Secure Boot feature, see the Secure Boot in Modern Computer Security Solutions [\"https://uefi.org/sites/default/files/resources/UEFI_Secure_Boot_in_Modern_Computer_Security_Solutions_2019.pdf\"] document.",
        "title": "Details"
      },
      {
        "category": "general",
        "text": "There are no workarounds that address this vulnerability.",
        "title": "Workarounds"
      },
      {
        "category": "general",
        "text": "Cisco has released free software updates that address the vulnerability described in this advisory. Customers may only install and expect support for software versions and feature sets for which they have purchased a license. By installing, downloading, accessing, or otherwise using such software upgrades, customers agree to follow the terms of the Cisco software license:\r\nhttps://www.cisco.com/c/en/us/products/end-user-license-agreement.html [\"https://www.cisco.com/c/en/us/products/end-user-license-agreement.html\"]\r\n\r\nAdditionally, customers may only download software for which they have a valid license, procured from Cisco directly, or through a Cisco authorized reseller or partner. In most cases this will be a maintenance upgrade to software that was previously purchased. Free security software updates do not entitle customers to a new software license, additional software feature sets, or major revision upgrades.\r\n\r\nWhen considering software upgrades [\"https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html#fixes\"], customers are advised to regularly consult the advisories for Cisco products, which are available from the Cisco Security Advisories and Alerts page [\"https://www.cisco.com/go/psirt\"], to determine exposure and a complete upgrade solution.\r\n\r\nIn all cases, customers should ensure that the devices to be upgraded contain sufficient memory and confirm that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) or their contracted maintenance providers.\r\n  Customers Without Service Contracts\r\n\r\n\r\nCustomers who purchase directly from Cisco but do not hold a Cisco service contract and customers who make purchases through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should obtain upgrades by contacting the Cisco TAC:\r\nhttps://www.cisco.com/c/en/us/support/web/tsd-cisco-worldwide-contacts.html [\"https://www.cisco.com/c/en/us/support/web/tsd-cisco-worldwide-contacts.html\"]\r\n\r\nCustomers should have the product serial number available and be prepared to provide the URL of this advisory as evidence of entitlement to a free upgrade.\r\n      Fixed Releases\r\nCustomers are advised to upgrade their appliances as indicated in the Remediation column of the following table:\r\n        Cisco Hardware Platform  First Fixed BIOS Version  First Fixed Cisco IMC Firmware Release\r\n  Remediation          FMC 1000, 2500, and 4500  4.0.1f.0  4.0.2h  Apply Hotfix CJ [\"https://www.cisco.com/c/en/us/td/docs/security/firepower/hotfix/Firepower_Hotfix_Release_Notes/available-hotfixes.html#Cisco_Reference.dita_c236fea7-4b1c-4952-bf42-41ee3ff2c5da\"].      Secure Network Server 3500  4.0.2d  4.0.2h  Apply the following patches:\r\n\r\nSNS-35xx-BIOS-4-0-2d-0_ISE.cap [\"https://software.cisco.com/download/home/283801620/type/283802505/release/SNS%2035x5\"]\r\nupd-pkg-SNS-35xx-cimc.full.4.0.2h.bin [\"https://software.cisco.com/download/home/283801620/type/283802505/release/SNS%2035x5\"]\r\n        Secure Network Server 3600  4.0.1i  4.0.1g  Apply the following patches:\r\n\r\nSNS-36xx-BIOS-4-0-1i-0_ISE.cap [\"https://software.cisco.com/download/home/283801620/type/283802505/release/SNS%2036x5\"]\r\nupd-pkg-SNS-36xx-cimc.full.4.0.1g.bin [\"https://software.cisco.com/download/home/283801620/type/283802505/release/SNS%2036x5\"]\r\n        Threat Grid 5504  4.0.2d  4.0.2h  Upgrade to Release 2.8.        Determine the BIOS Version and Cisco IMC Firmware Release\r\nCisco FMC 1000, 2500, and 4500\r\n\r\nTo determine the current BIOS version on a Cisco FMC, run the command sudo dmidecode -t bios -q from the Linux shell (expert mode). It is not possible to see the installed Cisco IMC firmware release, but the firmware will be upgraded as part of Hotfix CJ along with the BIOS firmware.\r\n\r\nCisco Secure Network Server\r\n\r\nThe current BIOS version and Cisco IMC releases are listed in the Admin \u003e Firmware Management section of the web-based management interface. The Cisco IMC firmware release is listed as BMC.\r\n\r\nCisco Threat Grid\r\n\r\nIt is not possible to see the current BIOS version. Instead, the Cisco Threat Grid software release needs to be verified because the Cisco IMC firmware will be upgraded as part of Cisco Threat Grid software release 2.8. The current build number is listed in the Operations \u003e Update Appliance section of the web-based management interface.",
        "title": "Fixed Software"
      },
      {
        "category": "general",
        "text": "To learn about Cisco security vulnerability disclosure policies and publications, see the Security Vulnerability Policy [\"https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html\"]. This document also contains instructions for obtaining fixed software and receiving security vulnerability information from Cisco.",
        "title": "Vulnerability Policy"
      },
      {
        "category": "general",
        "text": "The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.",
        "title": "Exploitation and Public Announcements"
      },
      {
        "category": "general",
        "text": "This vulnerability was found by Emre Demirors of Cisco during internal security testing.",
        "title": "Source"
      },
      {
        "category": "legal_disclaimer",
        "text": "THIS DOCUMENT IS PROVIDED ON AN \"AS IS\" BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME.\r\n\r\nA standalone copy or paraphrase of the text of this document that omits the distribution URL is an uncontrolled copy and may lack important information or contain factual errors. The information in this document is intended for end users of Cisco products.",
        "title": "Legal Disclaimer"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "Emergency Support:\r\n+1 877 228 7302 (toll-free within North America)\r\n+1 408 525 6532 (International direct-dial)\r\nNon-emergency Support:\r\nEmail: psirt@cisco.com\r\nSupport requests that are received via e-mail are typically acknowledged within 48 hours.",
      "issuing_authority": "Cisco product security incident response is the responsibility of the Cisco Product Security Incident Response Team (PSIRT). The Cisco PSIRT is a dedicated, global team that manages the receipt, investigation, and public reporting of security vulnerability information that is related to Cisco products and networks. The on-call Cisco PSIRT works 24x7 with Cisco customers, independent security researchers, consultants, industry organizations, and other vendors to identify possible security issues with Cisco products and networks.\r\nMore information can be found in Cisco Security Vulnerability Policy available at https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html",
      "name": "Cisco",
      "namespace": "https://wwww.cisco.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "Multiple Cisco UCS-Based Products UEFI Secure Boot Bypass Vulnerability",
        "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200219-ucs-boot-bypass"
      },
      {
        "category": "external",
        "summary": "Cisco Security Vulnerability Policy",
        "url": "https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html"
      },
      {
        "category": "external",
        "summary": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200219-ucs-boot-bypass",
        "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200219-ucs-boot-bypass"
      },
      {
        "category": "external",
        "summary": "Secure Boot in Modern Computer Security Solutions",
        "url": "https://uefi.org/sites/default/files/resources/UEFI_Secure_Boot_in_Modern_Computer_Security_Solutions_2019.pdf"
      },
      {
        "category": "external",
        "summary": "https://www.cisco.com/c/en/us/products/end-user-license-agreement.html",
        "url": "https://www.cisco.com/c/en/us/products/end-user-license-agreement.html"
      },
      {
        "category": "external",
        "summary": "considering software upgrades",
        "url": "https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html#fixes"
      },
      {
        "category": "external",
        "summary": "Cisco Security Advisories and Alerts page",
        "url": "https://www.cisco.com/go/psirt"
      },
      {
        "category": "external",
        "summary": "https://www.cisco.com/c/en/us/support/web/tsd-cisco-worldwide-contacts.html",
        "url": "https://www.cisco.com/c/en/us/support/web/tsd-cisco-worldwide-contacts.html"
      },
      {
        "category": "external",
        "summary": "Hotfix CJ",
        "url": "https://www.cisco.com/c/en/us/td/docs/security/firepower/hotfix/Firepower_Hotfix_Release_Notes/available-hotfixes.html#Cisco_Reference.dita_c236fea7-4b1c-4952-bf42-41ee3ff2c5da"
      },
      {
        "category": "external",
        "summary": "SNS-35xx-BIOS-4-0-2d-0_ISE.cap",
        "url": "https://software.cisco.com/download/home/283801620/type/283802505/release/SNS%2035x5"
      },
      {
        "category": "external",
        "summary": "upd-pkg-SNS-35xx-cimc.full.4.0.2h.bin",
        "url": "https://software.cisco.com/download/home/283801620/type/283802505/release/SNS%2035x5"
      },
      {
        "category": "external",
        "summary": "SNS-36xx-BIOS-4-0-1i-0_ISE.cap",
        "url": "https://software.cisco.com/download/home/283801620/type/283802505/release/SNS%2036x5"
      },
      {
        "category": "external",
        "summary": "upd-pkg-SNS-36xx-cimc.full.4.0.1g.bin",
        "url": "https://software.cisco.com/download/home/283801620/type/283802505/release/SNS%2036x5"
      },
      {
        "category": "external",
        "summary": "Security Vulnerability Policy",
        "url": "https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html"
      }
    ],
    "title": "Multiple Cisco UCS-Based Products UEFI Secure Boot Bypass Vulnerability",
    "tracking": {
      "current_release_date": "2020-06-01T13:56:07+00:00",
      "generator": {
        "date": "2022-09-03T03:00:37+00:00",
        "engine": {
          "name": "TVCE"
        }
      },
      "id": "cisco-sa-20200219-ucs-boot-bypass",
      "initial_release_date": "2020-02-19T16:00:00+00:00",
      "revision_history": [
        {
          "date": "2020-02-19T15:09:07+00:00",
          "number": "1.0.0",
          "summary": "Initial public release."
        },
        {
          "date": "2020-06-01T13:56:07+00:00",
          "number": "1.1.0",
          "summary": "Updated First Fixed Release for Secure Network Server 3600"
        }
      ],
      "status": "final",
      "version": "1.1.0"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "category": "product_family",
            "name": "Cisco Identity Services Engine Software",
            "product": {
              "name": "Cisco Identity Services Engine Software ",
              "product_id": "CSAFPID-111903"
            }
          },
          {
            "category": "product_family",
            "name": "Cisco Unified Computing System (Managed)",
            "product": {
              "name": "Cisco Unified Computing System (Managed) ",
              "product_id": "CSAFPID-112776"
            }
          }
        ],
        "category": "vendor",
        "name": "Cisco"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2019-1736",
      "ids": [
        {
          "system_name": "Cisco Bug ID",
          "text": "CSCvn09490"
        },
        {
          "system_name": "Cisco Bug ID",
          "text": "CSCvq27803"
        },
        {
          "system_name": "Cisco Bug ID",
          "text": "CSCvq27796"
        }
      ],
      "notes": [
        {
          "category": "other",
          "text": "Complete.",
          "title": "Affected Product Comprehensiveness"
        }
      ],
      "product_status": {
        "known_affected": [
          "CSAFPID-112776",
          "CSAFPID-111903"
        ]
      },
      "release_date": "2019-02-19T16:00:00+00:00",
      "remediations": [
        {
          "category": "vendor_fix",
          "details": "Cisco has released software updates that address this vulnerability.",
          "product_ids": [
            "CSAFPID-112776",
            "CSAFPID-111903"
          ],
          "url": "https://software.cisco.com"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 6.2,
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.0/AV:P/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.0"
          },
          "products": [
            "CSAFPID-112776",
            "CSAFPID-111903"
          ]
        }
      ],
      "title": "Multiple Cisco UCS-Based Products UEFI Secure Boot Bypass Vulnerability"
    }
  ]
}